Aaron Schaffhausen sits in courty during the second day of his trial at a St. Croix County Courtroom in Hudson, Wis., Wednesday, April 3, 2013. Schaffhausen is accused of the murder of his three daughters. (AP Photo/The Star Tribune, Elizabeth Flores) MANDATORY CREDIT; ST. PAUL PIONEER PRESS OUT; MAGS OUT; TWIN CITIES TV OUT
(The Associated Press)

Aaron Schaffhausen, back to camera, watches as jurors are shown a video of River Falls Police Detective Charles Golden initial interrogation of Schaffhausen during the second day of the trial at a St. Croix County Courtroom in Hudson, Wis., Wednesday, April 3, 2013. Schaffhausen is on trial for the murder of his three young daughters. (AP Photo/The Star Tribune, Elizabeth Flores) MANDATORY CREDIT; ST. PAUL PIONEER PRESS OUT; MAGS OUT; TWIN CITIES TV OUT
(The Associated Press)

HUDSON, Wis. – The mother of three girls who were killed by their father in what prosecutors say was an act of revenge testified Wednesday that her ex-husband was "catatonically depressed" but began taking medication and seemed to be getting better in 2011.

Aaron Schaffhausen has admitted to killing his three daughters, but claims he was not responsible due to mental illness. Jurors at his trial in St. Croix County will determine whether he was sane at the time of the slayings.

According to KSTP-TV (http://bit.ly/16wgsdG), Jessica Schaffhausen testified that she met Aaron in a coffee shop and that he was flunking school at the time.

She said he was happy "at times." She also said he dropped out of school because "he was feeling anxious about it and depressed, and I told him that he needed to get help, that he couldn't keep going on like this."

Jessica Schaffhausen said Aaron wasn't taking care of the kids or helping with chores and was playing video games for eight hours or more. She also said, "I would see him drinking every day, when I would see him." She said she told him that she wanted him to change or she would divorce him.

The Schaffhausens filed for divorce in August 2011. Aaron Schaffhausen would stay with the girls every other weekend when he was in the area, and Jessica Schaffhausen would go elsewhere.

Earlier Wednesday, jurors also watched a three-hour interview of Aaron Schaffhausen, recorded by police on the day of the killings.

During the first two hours, he is silent. In the final hour, he broke down crying as an investigator asked him about tucking the girls into their beds. When investigators asked if police should look for another suspect, he also shook his head and said, "No."

Later, he is seen on the videotape saying, "I don't know what I want; I don't know what I need. I want my girls back; I want a lot of things. Can you give them to me? Then quit offering the world like you have the keys." He later said, "I need help."

If Schaffhausen is found sane, he could go to prison for life. If the jury finds he was not responsible, he could be committed to a psychiatric institution and possibly be released at some point.